Scleroscope



E. C. LIPPS scLERoscoPE April 15 ,1924, 1,490,836

Filed Jan. 20. 1919 2 She`ets-Sheet 2 Patented Apr. 15, 1924.

UNITED STATES PATENT OFFICE.

EVRAH C. LIPPS, OF DETROIT, MICHIGAN, ASSIGNOR TO PACKARD MOTOR CAR COM- PANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

scLEnoscorn. y

Application led January 20, 1919.

To' all whom t may concern:

Be it known that I, EVRAH C. LIPPS, a citizen of the United States, and residing at Detroit, Wayne County, State of Michigan, have invented certain new and useful improvements in Soleroscopes, of which the following is a speciiication.

The present inventionrelates t0 scleroscopes or instruments for testing the relative hardness of materials and more particularly to the type of instrument having a hammer or striker adapted to be raised and thereafter dropped, the height of the rebound of the hammer being a measure of the hardness of the object tested.A

The principal features of the invention consist in the provision of an improved means to raise the hammer; the provision of improved means to hold the hammer raised and thereafter release the same; the provision of automaticallyacting means to raise and thereafter'release the hammer; 'the provision of means to intermittently raise and let fall the hammer; the provision of means to automatically place the tube in communication with the atmosphere after the hammer has been raised so that it may fall freely; and generally, to improve the construction and operation of this type of instrument. Gtherffeatures and objects of novelty will be apparent from the description taken in connection with the drawings in which ry Figure l is a front elevation of an instrument constructed in accordance with the present invention, the wiring and means for controlling the operation of the magnets being shown diagrammatically;

Figure 2 is a sectional elevation through the apparatus located at the top 0f the tube of the instrument; v

Figure 3 is a bottom plan view of the part of the instrument shown in Figure 2;

Figure 4f is a side elevation of the parts shown in Figure 2, certain parts being broken away to illustrate the arrangement of the wires, this figure being on a reduced scale;

Figure 5 is a side elevation illustrating the switch mechanism disposed vat the lower end of the tube; i

Figure 6 isl a. sectional view taken substantially on the line 6-6 of Figure l5;

Serial No. 272,080.

Figure 7 is a diagrammatic view illustrating the electric circuits'4 and means for conf y10 indicates a plate supported by the three adjusting screws `l1 and carrying an anvil l2. A postl lprojects vertically from the anvil and adjustably supports a frame 14 carrying' a glass tube or guide l5 within which is slidinoly fitted a hammer or striker 1,6. As shown, this hammer is in the form of a ball although other types of strikers may be employed. The frame 14: is adapted to be adjusted vertically by means of the thumb .screw 17 which operates any suitable mechanism for this purpose. The parts described above may be `constructed and arranged as disclosed by the patent to Shore, 962,790, June 28, 19l0.

In the operation ofthe instrument the hammer 16 is raised and then allowed to fall onto the material being tested, the eX- ent of the rebound indicating the degree of hardness of the material. According to the present invention novel means are provided for raising the hammer. and thereafter releasing it. This means is illustrated in vertical section in rFigure 2 and is adapted to be disposed at the upper end of the tube 15.1 For this purpose a sleeve 18 is formed witn a nipple 19 which fits into the upper end of' the tube and the bore 20 of this sleeve communicates with the interior of the tube. The sleeve also has a radially extending flange 2l formed with aperipheral lip 22 which engages and holds the lower end of a casing 23 enclosing the apparatus. The sleeve 18 at its upper end is formed with a threaded nipple Qetwhich is screwed into the lower endy of a sleeve 25 formed with avbore 26 which constitutes an extension of the bore 20. The upper end of the sleeve 25 has a threaded nipple 27 which carries a cylinder 28. The nipple 2T has a portion 39 which is unthreaded and projects into the cylinder, communication between the bore 26 and the cylinder being had through radial ports formed in this extension 29. It will be seen, therefore, that the cylinder :'28 has communication with the interior of lil@ Y of its stroke, the stem ,34 having a stem 35 the tube 15 through the bores of the sleeves. For the purpose-of reducing the air pressure above the hammer 16 and thereby raising the' same, a plunger or piston 31 is slidingly fitted in the cylinder 28. When this plunger is raised, it is obvious that the air pressure below the same and in the tube 15 is reduced thus raising the hammer. As shown, the plunger 31 is in the form of a sleeve having a head 32 set in at one end of the sleeve. This head is formedwith a plurality of passages 33 adapted to be closed by a valve which projects below the head 32. `When the plunger moves upwardly the va-lve 34 is held against the head 32 by gravity and thus closes the openings When the plunger 31-falls,'near the end strikes the eXtension-29, thereby raising the valve 34 and opening the passages 33. In this manner communicationis aiforded between the interior'of the tube 15 and the atmosphere, in consequence of which the hammer may fall freely. I

' For the purpose of operating the plunger 31'an electromagnet 36 is disposed around the upper portion of the cylinder 28. Vhen this magnet is energized the plunger 31 moves upwardly thereby reducing the air pressure in the tube 15 and raising the hammer. For the purpose of holding the hammer in raised position until the plunger 31 may fall, an electro-magnet 37 is disposed around the sleeve 18. When this magnet is energized and the hammer is in raised position, it will hold the hammer against the lower tip end 33 of the sleeve, this end being preferably of brass in order to eliminate any effects of residual magnetism.

Preferably, the magnets are controlled so that the hammer is intermittently raised and released. To this end a pair of rotary switches 39 and 40 V(Figure 7 are provided. As shown these switches consist of disks or cominutators mounted on a shaft 41 rotated in any suitable manner, as by means Current' is talren from a of a motor 42. main and by means of wire 43 conducted to the segment 44 of switch 39. This segment is an electrical conductor and is insulated from the rest of the disk. A brush or other conductor 45 is positioned to engage Y the segment 44 as it rotates and is connected Yto the magnet 36 through conductor 46.V

From the magnet the current may flow through a return wire 47 to a terminal 48 of a switch presently to be described. From the other terminal 49 of this switch the current flows through a wire 50 to the other supply main. Tn this manner the switch 39 controls the operation of the electromagnet 36.

The switch 40 in asimilar manner controls the operation ofthe electro-magnet 37. Thus the current may be taken from the wire 43 to the segment 51 which is Y an electrical conductor and insulated from the remainder of the rotary switch. A brush 52 is disposed to contact with the segment as it rotates and is electrically connected to the magnet 37 by means of conductor 53. The circuit continues through the common return 47 to the switch terminal 48.

Preferably, the timing of the energizing of the two magnets is such that the magnet 37 is irstsupplied with current, and immediately thereafter the magnet 36 is energized which, through the operation of the plunger31, raises the hammer. The mawnet 37 being energized, the hammer is held against the tip 38.V The magnet 36 is now (le-energized' thus permitting the plunger 31 to fall and open the valve 34 thereby placing the passages above the hammer in communication with the atmosphere so that the hammer may fall freely. rThe magnet 37 may now be cle-energized thus permitting the hammer to fall. This cycle of operations is then repeated with the result that the ball is raised and allowed to fall at regular intervals so that the operator may obtain an accurate reading of the rebound of the hammer. Referring to Figure 7 it will be observed that the segments 44 and 51 are disposed and are of such extent that if the lswitches are rotating in the direction indicated by the arrow a, the magnet 37 will first be energized, then magnet 36. But las as segment 44 is less than one-half the length of segment 51, magnet 36 will soon thereafter be demagnetized and later magnet 37 will also be rendered inoperative. To illustrate, if the shaft 41 makes one revolution every three seconds the ntent of segment '51 mightv be such as to maintain the magnet 37 energized for about two seconds while the, segment 44 maintains theV magnet 36 energized for three-fourths of a second and such energization takes place about onefourth of a second afterthe energizing of magnet 37.

From the foregoing it will be seen that automatic means are provided for intermittently raising-and allowing the hammer to fall. For the purpose of further controlling this automatic nieans the switch having the contacts 48 and 49 is provided and preferably this switch is disposed so that it is closed when the tube 15 is -lowered onto the test piece. Referring now to Figures 5 and 6 it will be seen'that at the lower end of the tube 15 the frame 14V is formed Vwith Yan offset 531 which carries the contact 48. The contact 49 is mounted on an arm 54 carried by a lever 55 disposed at the lower end of the tube 15 and pivotally mounted as at 56 on the offset 53. It will be seen that the arrangement of these parts is such that when the tube 15 is lowered the lever 55, which is in the form'of a closed figure kzo surrounding thetube 15, will strike thev test piece and move the contact ,49 into engagement with the contact 48. Preferably, they contact 49 is yieldingly mounted so that the circuit through theswitch will be. properly maintained. p Y

' Referring now to Figures2`and 4 Yit will be seen that the wires 46, y47 and 53 previously mentioned are brought to binding posts 57 on the flange 21. `Thence they extend upward, being disposed in the slots 58 formed in the sleeve 18. f Just above the magnet 37 these wires are carriedl to the collar 59 secured to the sleeve 25 and from this collar extend to theirjrespective magnets. i f 1 In the operation of the instrument the tube 15 being Lraised the testy piece is placed on the anvil 12 and thetube lowered into contact with the same. The lever is thereby turned on its pivot to bring the contact 49 intoengagement with the contact 48 and set in loperation the motor 42. This energizes magnet 37 and immediately thereafter magnetv 36 which raises the hammer and holds. Ait until the magnet 37 is demagnetized. During this holding period the upper end of the' tube has been placed in communication with the atmosphere so that the hammer may all freely. This cycle of operations will -be repeated as long as the switch at the lower end of the tube is kept closed or` until the test piece is withdrawn from the instrument.

If desired, the instrument may be equipped tobe controlled manually. The wiring for such control gis illustrated diagrammatically inFigure 8. Thus the magnet.36. has a conductor 46which extends to a springcontact Y It is also connected with a common ref turn 47) by conductor 60. t The magnet 37 is connected by means of a conductor 53 with a contact 52 disposed at one side of the contact 45. This magnet is also connected'tothe common return 47 by a wire 61. A con- A ytact 62 is disposed on the opposite side'or' contact 45 with-respect tol 52'.. As shown, the contact 62 is carried' at one end of a lever or key 63 pivotally mounted at 64, a spring 65 being provided tohold the contact -62 out of engagement with the other contacts. N hen the lever 63 isdepressedit carries the contact 62 into engagement with contact 45', thereby energizing the lower magnet 37. Thereafter the contacts 45 and 62 remaining in engagement are carried as a unit against the contact 52 thereby energizing the magnet 36. Thus the magnet 37 is firstmagnetized and immediately there-V after magnet 36. The circuits are broken in the reverse order so that the magnet 36 is znetizved first. Although an embodiment of -the invention has been described in detail it is to be understood that the invention is notthus limited when open, to place the tube in communication with the atmopshere, a second electromagnet disposed below said cylinder adapted' when energized to hold the hammer raised, and means to open said valve when f the plunger falls.

2. In a scleroscopethe combination with the tube and hammer slidably fitted therein; of a cylinder at the top of the tube in communication with the tube, a plunger in ysaid cylinder having a passage ati'ordingy communication between the tube and atmosphere, a valve controlling saidpassage having a stem projecting at one end of the plunger, means to move said plunger in one direction to reduce the air pressure in the tube, and means engaging said stem to open the valve when the plunger moves in the opposite direction. n. i 3. In a scleroscope the combination with the tube and hammer slidably fitted therein; of avertically disposed cylinder at the top of the tube in communication therewith, a

plunger in said cylinder, having a valve controlled axial passage therethrough, means to raise said plunger to reduce the air pressure in the tube, and means to open said valve after the plunger has completed its upward movement to place the tube in communication with they atmosphere. i

4. In a scleroscope the combinationwith the tube and hammer slidably fitted therein;

of a single acting pump at the top. of the tube in communication therewith, comprising a cylinder, and a plunger kin said cylin-y v der, .means to actuate said plunger to reduce the air pressure 1n the tube, and means operated by the return movement of the plunger to place the tube in communication with the atmosphere.` i 5. In a scleroscope .the combination with the tube and hammerslidably fitted therein; of a cylinder at the top of the tube in communication therewith. a plunger in said cylinder, and an electro-magnet to move said plunger in thedirection to reduce the air pressure in the tube. l

6. A scleroscope comprising in combination, a Vertical guide, a hammer slidably associated therewith, 4electro-magnetic means to raise the hammer, electro-magnetic means Y in circuit with each of 'said means, V

8. A scleroscope comprising in combination, a vertical guide, a hammer slidably associated therewith,'electromagnetically opkio 'erated pneumatic means to raise the fhammer, a switch in circuit with said lmeans,ar 1d Vmeans independent lof Vsaid hammer'to 1ntermittently open and closesaidlswitch.'

'9. AV scleroscopel comprising in combination, a Vertical guide, a hammernslidably associated therewith, lpneumatic means to raise the hammer and thereafter drop it,

'and controlling ineans independentor said hammer to repeatedlyelect the operation of 'the iirst mentioned means.

10. A scleroscope comprising incombination, a guide .mounted for vertical adjustment to place thetest pieceunder its'lower end, a hammerslidably associatedwith said guide, electric means vto `lraise the hammer,

hold it raised andy thereafter release rit,

Vmeans to control the operation of said electric means including a switch l in `circuit therewith adapted .to be closed by thegadjustment ofthe .guide toward the 'test lpiece.

'114A scleroscope comprising 'combination, a vertical guide, la hammer "slidably associated therewith, .electric .means toraise tion, a guide,

the hammer, electric means to hold thezhainmer raised and thereafter release it, means to control the operation of said electric' means including a switch in circuit therewith adapted to be opened bywithdrawing the test piece from the instrument. 'i

12. A scleroscope comprising incombination, .a Vertical guide, ya 4hammer Aslidably associated therewith, electric meansto raise ,theY hammer, electric means to"hold"'the hainmer raised and thereafter'releaseitfa switch to control the raising means, a switch to control the holding means, andV means tofclose said switches in the sequence recited.

' 13. VA scleroscope comprising incombinaa hammer Aslidaloljy associated therewith,.electric means to raise the hammer, electric l,means to Vhold the hammer raised and thereafter release it,'and con-- trol means to render said electric means voperative inthe sequence recited.Y

14'. A scleroscope comprising lin combination, a vertical guide, fa hammer "slidably associated therewith, means to yraise the ham-v mer, means to hold thefhammerraised and Y thereafterrelease it, and "controly'meafii'sv ito rendersaid raising and holding means operative inthe sequence recited. '15."As'cleroscope comprising in combination, Va fvertical guide, a hammer slidably yassociated therewith, means to adjustably support the guide so that the test piece may Vbe inserted under the lower end thereof, means to raise the hammer, and means to 'hold yit raised, said raising and holding means being rendered operative by lowering "the guide onto the `test piece.'

"16. A scleroscope comprising in combination, a'tube, a hammer slidably iitted therein, y,means toreduce" the air pressure inthe tube above Atheha-"mmer to raise `the hammer, means to'hol'd the'hammerraised, and means to thereafter put the tube above the raised fhaminer in "communication-with the atmosphere and lrelease the holding `means. v"`""17. vAsc'lero'scope comprising in combination, a 'vertical guide, a hammer yslida'bl) `associatedtherewith,meansV to raise the-hammer, means fto*V hold lit raised, and automatic 'means controlling the operation of said rais- 'ing and vholding means.

voperating electro-magnetic means Vto `hold the hammerraised fand' thereafter release the same. Y Y `{19.11A}scleroscope comprising in combinaa combination,`- a tube, affhammer slidable therein,

`means to reduce the air pressure in the tube to Vraisejthe hammer, and automatically operating means-to ho'ld the hammer raised .andfthereafter releasethe s aine.

V20'. Ascleroscope comprising in combination, atu'be, a Vhammer slidableY therein, means -"to` reduce fthe air pressurev in the ntube/"to vraiseithe hammer, and electro-mag-y ynetic'means to'hold thehammer raised.'

Ay scleroscope comprising in combination, a Vertical fg'uide, a hammer of `less V'length thanth'e guide` associated therewith, electro-magnetic means to raise said'hammer to "the top ofthe guide,lan^d electro-magnetic meansV lto "hold ythe jhammer raised.

'22. A scleroscope comprising in combination, a vertical guide, a hammer of less length than said guide associated therewith,

means to raise the hammer to the top of the guide, and electro-magnetic means to hold the hammer raised.

123. A scleroscope comprising in combination, a Vertical guide, a 'hammer of less Vlength than saidguide associated therewith, electro-magnetic means to raise said hammer to the top of the guide, means to hold the hammer raised', and means to release said holding meansto permit'the hammer to tall.

24. A scleroscopepcomprisin in* combination,fa verticallyadjustableguide, a hammer slidably associated therewith, electric means to raise the hammer, mea-ns to control the operation of said electric means including a switch in circuit therewith adapted to be closed by the adjustment of said guide.

25. In a scleroscope the combination with the tube and hammer slidably fitted therein; oi a cylinder at the top of the tube in coinmunication therewith, a plunger yieldingly held at one end of said cylinder, an electromagnet to move the plunger away from said end to reduce the air pressure in the tube below atmospheric and thereby raise the hammer, said plunger having avalve controlled passage therethrough, adapted when open to place the tube in communication with the atmosphere, a second electro-magnet adapted when energized to hold the hammer raised and means to open said valve when the plunger moves toward the said end of the cylinder. l

26. In a scleroscope the combination with the tube and hammer slidably fitted therein; of a cylinder at the top of the tube in communication therewith, a plunger yieldingly held at one end of the cylinder, an electromagnet adapted to move the plunger away from said end to reduce the air pressure in the tube below atmospheric and thereby raise the hammer, a valve controlled passage adapted to place the tube in communication with the atmosphere, said valve being open when the plunger is at said end of the cylinder and closed at other times, releasable means to hold the hammer raised and means to open said valve when the plunger moves toward said end.

27. In a scleroscope the combination with the tube and hammer slidably fitted therein; of a cylinder at the top of the tube in communication therewith, a plunger yieldingly held at one end of said cylinder having a valve controlled passage therethrough, means to move said plunger away from said end to 'reduce the air pressure in the tube and means to open said valve after the plunger has completed said movement, to thereby place the tube in Comunication with the atmosphere.

In testimony whereof I aiix my signature.

EVRAH C. LIPPS. 

